Tallahassee, Florida - Gov. Rick Scott and leaders of Florida ports are urging President Obama to take action to prevent a possible strike by port workers this weekend.

The contract for members of the International Longshoremen's Association is set to expire Saturday night. The ILA is negotiating with the United States Maritime Alliance.

Gov. Scott says a strike by thousands of longshoremen could affect 550,000 jobs in Florida and send shockwaves through the state's economy. He says transporting cargo shipments generates $66 billion a year in Florida.

"If a strike or lockout occurs at that time, Florida's largest ports could be shut down, sending shockwaves through jobs all across our state, including transportation jobs like truck drivers, locomotive engineers, container ship jobs, manufacturing jobs, warehousing jobs, and many other jobs beyond the ports themselves."

Scott and port leaders are calling on the president to invoke the Taft-Hartley Act to prevent a work stoppage at ports. That measure orders a cooling off period and mediation in contract talks.

"Our message to President Obama is simple: a shutdown of Florida ports is simply not an option for Florida families. We need the federal government, President Obama, to support Florida ports as we have done at the state level," said Gov. Scott.

Port of Tampa CEO Paul Anderson echoes the governor's call for President Obama to intervene if a strike happens.

Anderson warns that a longshoremen's strike, combined with the pending federal fiscal cliff, would have devastating economic consequences.

"A strike this Saturday, combined with the ongoing negotiations between Congress and President Obama regarding the so-called fiscal cliff could be a one-two combination knockout punch for our nation's economy."

JAXPORT Chief Operating Officer Chris Kauffmann says he's concerned about a disruption in business because JAXPORT is so crucial to the economy in northeast Florida.

"We have a significant yearly dollar impact to the northeast Florida economy like everyone else. Ours is roughly $19 billion on an annual basis and when you look at all the jobs that are supported by all the various operations here in Jacksonville, we affect 65,000 jobs in northeast Florida so there is a tremendous impact upon all of the supply chain associated with the trade."

Gov. Scott says the strike could shut down Florida ports and cost the nation's economy more than $1 billion a day.